Electrical power supplies provide electrical energy for a variety of applications. Often, power supplies receive electrical energy from a source, such as a generator, and convert that electrical energy to an application-specific form. For example, a power supply may receive electrical energy as alternating current (“AC”) and convert that electrical energy to direct current (“DC”). The power supply may then provide the DC electrical energy to a device (e.g., a “load”) to operate the device. Lower voltage power supplies are routinely built at voltages up to 10V and, in some instances, output arbitrary and/or pre-programmed waveforms as a function of time.
Higher-voltage power supplies are generally those power supplies providing electrical energy at voltages of greater than 100 volts, often having more unique applications than their lower voltage counterparts. For example, high-voltage pulsed power supplies may be used in certain types of ion implantation, such as Plasma Source Ion Implantation (“PSII”) and/or Shallow Implantation and Diffusion Hardening (“SIDH”). In this regard, such power supplies may be used to control doping profiles in semiconductors.
In PSII, a target (e.g., a silicon wafer) is placed directly inside an ion source. High voltage negative pulses applied to the target attract positive ions in the plasma and thereby strike the target at normal angles of incidence. Similarly, in SIDH, the target is immersed in a plasma and pulsed with high-voltage electrical energy. The pulsing of the electrical energy allows ions from the plasma to penetrate within the target. By varying the voltage, the depth dose profile can be varied. High-voltage power supplies, however, are not limited to such applications. Rather, high-voltage power supplies may be used in a variety of applications, such as plastic curing and medical imaging (e.g., x-rays).